Pediatric cardiac arrest is not a single problem. Although most episodes of pediatric cardiac arrest occur as complications and progression of respiratory failure and shock. Sudden cardiac arrest may result from abrupt and unexpected arrhythmias. With a better-tailored therapy, we can optimize the outcome. In the hospital, cardiac arrest often develops as a progression of respiratory failure and shock. Typically half or more of pediatric victims of in-hospital arrest have pre-existing respiratory failure and one-third or more have shock, although these figures vary somewhat among reporting hospitals. When in-hospital respiratory arrest or failure is treated before the development of cardiac arrest, survival ranges from 60% to 97%. Bradyarrthmia, asystole or pulseless electric activity (PEA) were recorded as an initial rhythm in half or more of the recent reports of in-hospital cardiac arrest, with survival to hospital discharge ranging from 22% to 40%. Data allowing characterization of out of hospital pediatric arrest are limited, although existing data support the long-held belief that as with hospitalized children, cardiac arrest most often occurs as a progression of respiratory failure or shock to cardiac arrest with bradyasystole rhythm. Although VF (Ventricular fibrillation, is a very rapid, uncoordinated, ineffective series of contractions throughout the lower chambers of the heart. Unless stopped, these chaotic impulses are fatal) and VT (Ventricular tachycardia is a rapid heartbeat that originates in one of the ventricles of the heart. To be classified as tachycardia, the heart rate is usually at least 100 beats per minute) are not common out-of-cardiac arrest in children, they are more likely to be present with sudden, witnessed collapse, particularly among adolescents. Pre-hospital care till the late 1980s was mainly concerned with adult care, and the initial focus for pediatric resuscitation was provision of oxygen and ventilation, with initial rhythm at the time of emergency medical services arrival being infrequently recorded. In the 1987 series, pre-hospital pediatric cardiac arrest demonstrated asystole in 80%, PEA in 10.5% and VF or VT in 9.6%. Only 29% arrests were witnessed, however, and death in many victims was caused by sudden infant death syndrome.